Excess body fat, or adipose tissue, may be present in various locations of the body, including, for example, the thigh, buttocks, abdomen, knees, back, face, arms, chin, and other areas. Excess adipose tissue can detract from personal appearance and athletic performance. Moreover, excess adipose tissue is thought to magnify the unattractive appearance of cellulite, which forms when subcutaneous fat lobules protrude and penetrate into the dermis and create dimples where the skin is attached to underlying structural fibrous strands. Cellulite and excessive amounts of adipose tissue are often considered to be unappealing. Moreover, significant health risks may be associated with higher amounts of excess body fat.
Adipose tissue is subdivided into lobules by connective collagen tissue called fibrous septae. The fibrous septae, which are generally oriented perpendicular to the skin surface and anchor the epidermis and dermis to the underlying fascia and muscle, are organized within the subcutaneous layer to form a connective web around the adipose cells. Subcutaneous adipose cells are not uniformly distributed throughout the subcutaneous tissue layer (e.g., between the dermis and the muscle layers), but exhibit regional differences in lobule size and shape. These regional differences can, in part, be due to gender, age, genetics and physical conditioning among other physiological factors. The number, size, distribution and orientation of fibrous septae also vary by body location, gender and age. For example, histological studies have shown that fibrous septae architecture in women differs from that in men.
In males, fibrous septae form a network of cris-crossing septa of connective tissue that divide fat-cell chambers into small, polygonal units. In contrast, fibrous septae in females generally tend to be oriented perpendicular to the cutaneous surface, tending to create “fat cell chambers” or “papillae adiposae” that are columnar in shape and sequestered by the connective strands and the overlaying dermis layer. When the fibrous septae are more uniform in size and elasticity as well as positioned evenly throughout the subcutaneous layer, such as those characteristic of males, tension and stress is distributed evenly among the connective strands and the adipose cells are largely contained within the web of collagen. However, the subcutaneous fat cell chambers characteristic of females can bulge into the dermis, thereby changing the appearance of the skin surface. Added weight (e.g., fat cell lipid volume) may cause enlargement of the fat lobules, which can then further protrude into the dermis. Nümberger, F., Müller, G., “So-Called Cellulite: An Invented Disease” J. Dermatol. Surg. Oncol. 4:3, 221-229 (1978).
Cellulite (Gynoid lipodystrophy) is typically a hormonally mediated condition characterized by the uneven distribution of adipose tissue in the subcutaneous layer that gives rise to an irregular, dimpled skin surface common in women. Cellulite-prone tissue can be characterized by the uneven thickness and distribution of some fibrous septae strands. Thicker strands can continue to act as a buttress to herniation and bulging of the adipose chambers into the dermis; however, thinning strands near the dermal layer permit the adipocytes to bulge into and penetrate the dermal layer, and in some cases cause thinning of the dermal layer. In exacerbated conditions of cellulite, fat lobules are enlarged near the dermal layer with excessive stored lipids and bound only by thin and focally loose connective tissue strands. Piérard, G. E., Nizet, J. L, Piérard-Franchimont, C., “Cellulite: From Standing Fat Herniation to Hypodermal Stretch Marks,” Am. J. Dermatol. 22:1, 34-37 (2000).
Various non- and minimally invasive treatment modalities have been offered for improving the appearance of cellulite, including cold therapy, the use of heating such as by radio frequency, microwave, or laser energy, the use of focused ultrasound energy, mesotherapy, and other techniques.
A variety of similar and identical methods have been used or offered to treat individuals having excess body fat and, in many instances, non-invasive removal of excess subcutaneous adipose tissue can eliminate unnecessary recovery time and discomfort associated with invasive procedures such as liposuction. Conventional non-invasive treatments for removing excess body fat typically include topical agents, weight-loss drugs, regular exercise, dieting, or a combination of these treatments. One drawback of these treatments is that they may not be effective or even possible under certain circumstances. For example, when a person is physically injured or ill, regular exercise may not be an option. Similarly, weight-loss drugs or topical agents are not an option when they cause an allergic or negative reaction. Furthermore, fat loss in selective areas of a person's body often cannot be achieved using general or systemic weight-loss methods.
Other methods designed to reduce subcutaneous adipose tissue include laser-assisted liposuction and mesotherapy. Non-invasive methods include applying radiant energy to subcutaneous lipid-rich cells via, e.g., radio frequency and/or light energy, such as described in U.S. Patent Publication No. 2006/0036300 and U.S. Pat. No. 5,143,063, a high intensity focused ultrasound (HIFU) radiation such as described in U.S. Pat. Nos. 6,071,239, 7,258,674 and 7,347,855. Additional methods and devices for non-invasively reducing subcutaneous adipose tissue by cooling are disclosed in U.S. Pat. No. 7,367,341 entitled “METHODS AND DEVICES FOR SELECTIVE DISRUPTION OF FATTY TISSUE BY CONTROLLED COOLING” to Anderson et al. and U.S. Patent Publication No. 2005/0251120 entitled “METHODS AND DEVICES FOR DETECTION AND CONTROL OF SELECTIVE DISRUPTION OF FATTY TISSUE BY CONTROLLED COOLING” to Anderson et al. The entire disclosures of the references listed in this paragraph are incorporated herein by reference.
The process of treating a patient having excess body fat and/or cellulite with one or more of non-invasive and/or minimally invasive techniques can include several preparative and planning stages. For example, a preliminary examination and assessment of the region to be treated is required. This preliminary examination is followed by development of a treatment prescription by a medical professional.